Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
J Natl Med Assoc ; 113(6): 599-611, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34158171

RESUMO

BACKGROUND: National data indicate low intentions for COVID-19 vaccination among a substantial minority of Black Americans, and disproportionately lower vaccination rates among Black Americans than White Americans. METHODS: A total of 207 of the 318 Black participants (65%) in the RAND American Life Panel, a nationally representative internet panel, were surveyed about COVID-19 vaccine intentions in November-December 2020. Participants' census tracts were geocoded using the Centers for Disease Control and Prevention's Social Vulnerability Index. RESULTS: Overall, 35% agreed or strongly agreed that they would not get a COVID-19 vaccine, 40% agreed or strongly agreed that they would get vaccinated, and 25% reported "don't know." Significant multivariable predictors of not wanting to get vaccinated included high mistrust of the vaccine itself (e.g., concerns about harm and side effects), OR (95% CI) = 2.2 (1.2-3.9), p = .007, and weak subjective norms for vaccination in one's close social network, OR (95% CI) = 0.6 (0.4-0.7), p < .001. Residence in an area of higher socioeconomic vulnerability was a marginally significant predictor, OR (95% CI) = 3.1 (0.9-11.0), p = .08. CONCLUSIONS: High mistrust around COVID-19 vaccines may lower vaccine confidence. Social network members' attitudes can be influential in encouraging vaccination. Public health communications could use transparent and clear messaging on safety and efficacy, and acknowledge historical and ongoing discrimination and racism as understandable reasons for low confidence in COVID-19 vaccines. Future research is needed to consider vaccine access challenges in tandem with mistrust as contributing to low vaccination rates across health conditions.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Negro ou Afro-Americano , Humanos , Intenção , SARS-CoV-2 , Estados Unidos
2.
Cannabis Cannabinoid Res ; 6(6): 508-521, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34142866

RESUMO

Background: The endogenous cannabinoid system modulates inflammatory signaling in a variety of pathological states, including traumatic brain injury (TBI). The selective expression of diacylglycerol lipase-ß (DAGL-ß), the 2-arachidonylglycerol biosynthetic enzyme, on resident immune cells of the brain (microglia) and the role of this pathway in neuroinflammation, suggest that this enzyme may contribute to TBI-induced neuroinflammation. Accordingly, we tested whether DAGL-ß-/- mice would show a protective phenotype from the deleterious consequences of TBI on cognitive and neurological motor functions. Materials and Methods: DAGL-ß-/- and -ß+/+ mice were subjected to the lateral fluid percussion model of TBI and assessed for learning and memory in the Morris water maze (MWM) Fixed Platform (reference memory) and Reversal (cognitive flexibility) tasks, as well as in a cued MWM task to infer potential sensorimotor/motivational deficits. In addition, subjects were assessed for motor behavior (Rotarod and the Neurological Severity Score assays) and in the light/dark box and the elevated plus maze to infer whether these manipulations affected anxiety-like behavior. Finally, we also examined whether brain injury disrupts the ceramide/sphingolipid lipid signaling system and if DAGL-ß deletion offers protection. Results: TBI disrupted all measures of neurological motor function and reduced body weight, but did not affect body temperature or performance in common assays used to infer anxiety. TBI also impaired performance in MWM Fixed Platform and Reversal tasks, but did not affect cued MWM performance. Although no differences were found between DAGL-ß-/- and -ß+/+ mice in any of these measures, male DAGL-ß-/- mice displayed an unexpected survival-protective phenotype, which persisted at increased injury severities. In contrast, TBI did not elicit mortality in female mice regardless of genotype. TBI also produced significant changes in sphingolipid profiles (a family of lipids, members of which have been linked to both apoptotic and antiapoptotic pathways), in which DAGL-ß deletion modestly altered levels of select species. Conclusions: These findings indicate that although DAGL-ß does not play a necessary role in TBI-induced cognitive and neurological function, it appears to contribute to the increased vulnerability of male mice to TBI-induced mortality, whereas female mice show high survival rates irrespective of DAGL-ß expression.


Assuntos
Lesões Encefálicas Traumáticas , Lipase Lipoproteica , Animais , Lesões Encefálicas Traumáticas/genética , Feminino , Lipase Lipoproteica/genética , Masculino , Camundongos , Camundongos Knockout , Microglia , Doenças Neuroinflamatórias
3.
Behav Processes ; 161: 139-148, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29462649

RESUMO

Beginning in the 1950s, B.F. Skinner made increasing reference to an analogy between operant conditioning and natural selection. This analogy is the basis of an argument that, in contrast to Skinner's other critiques of cognitive science, is neither epistemological nor pragmatic. Instead, it is based on the claim that ontogenetic adaptation is due to a special mode of causation he called "selection by consequences." He argued that this mode of causation conflicts with explanations that attribute action to an autonomous agent with reasons for acting. This argument dismisses ordinary explanations of action, and has implications not only for cognitive science but also for morals. Skinner cited the latter implications to counter objections to the application of behavior analysis to the reform of society and its institutions. Skinner's critique, however, rests upon empirical assumptions that have been criticized by other behavior analysts. Although for Skinner the major role of the analogy was to propose an empirical thesis, it also can play a metaphysical role-namely, to demonstrate the possibility of ontogenetic adaptation without reference to agents who have reasons for acting. These two roles, empirical and metaphysical, are the mirror image of the empirical and metaphysical roles of the computer analogy for cognitive science. That analogy also can be (and has been) interpreted as an empirical thesis. Its empirical implications, however, have been difficult to confirm. It also, however, has played a metaphysical role-namely, to demonstrate the possibility that a physical process could perform logical operations on states having propositional content. Neither analogy provides a well-confirmed, general answer to the question of how to explain the process of ontogenetic adaptation. But together they show there are two metaphysically coherent, but conflicting, answers to this question. Depending upon one's epistemology, the analogy with natural selection may provide a useful point of departure for a strategy of research. Such a pragmatic grounding for a research strategy does not, however, provide sufficient reason to abandon for purposes of ethics the concept of persons as autonomous agents.


Assuntos
Condicionamento Operante , Seleção Genética , Comportamento , Causalidade , Humanos , Conhecimento , Metafísica , Autonomia Pessoal , Filosofia , Teoria Psicológica , Pesquisa
4.
J Neurotrauma ; 36(10): 1615-1631, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30444175

RESUMO

Olfactory receptor axons reinnervate the olfactory bulb (OB) after chemical or transection lesion. Diffuse brain injury damages the same axons, but the time course and regulators of OB reinnervation are unknown. Gelatinases (matrix metalloproteinase [MMP]2, MMP9) and their substrate osteopontin (OPN) are candidate mediators of synaptogenesis after central nervous system (CNS) insult, including olfactory axon damage. Here, we examined the time course of MMP9, OPN, and OPN receptor CD44 response to diffuse OB injury. FVBV/NJ mice received mild midline fluid percussion insult (mFPI), after which MMP9 activity and both OPN and CD44 protein expression were measured. Diffuse mFPI induced time-dependent increase in OB MMP9 activity and elevated the cell signaling 48-kD OPN fragment. This response was bimodal at 1 and 7 days post-injury. MMP9 activity was also correlated with 7-day reduction in a second 32-kD OPN peptide. CD44 increase peaked at 3 days, delayed relative to MMP9/OPN response. MMP9 and OPN immunohistochemistry suggested that deafferented tufted and mitral neurons were the principal sites for these molecular interactions. Analysis of injured MMP9 knockout (KO) mice showed that 48-kD OPN production was dependent on OB MMP9 activity, but with no KO effect on CD44 induction. Olfactory marker protein (OMP), used to identify injured olfactory axons, revealed persistent axon damage in the absence of MMP9. MMP9 KO ultrastructure at 21 days post-injury indicated that persistent OMP reduction was paired with delayed removal of degenerated axons. These results provide evidence that diffuse, concussive brain trauma induces a post-injury interaction between MMP9, OPN, and CD44, which mediates synaptic plasticity and reinnervation within the OB.


Assuntos
Concussão Encefálica/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Plasticidade Neuronal/fisiologia , Bulbo Olfatório/patologia , Osteopontina/metabolismo , Animais , Concussão Encefálica/patologia , Receptores de Hialuronatos/metabolismo , Camundongos , Camundongos Knockout , Neurogênese/fisiologia , Bulbo Olfatório/metabolismo , Sinapses/metabolismo , Sinapses/patologia
5.
Neuroscience ; 371: 106-118, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29203228

RESUMO

Despite the regenerative capacity of the olfactory bulb (OB), head trauma causes olfactory disturbances in up to 30% of patients. While models of olfactory nerve transection, olfactory receptor neuron (ORN) ablation, or direct OB impact have been used to examine OB recovery, these models are severe and not ideal for study of OB synaptic repair. We posited that a mild fluid percussion brain injury (mFPI), delivered over mid-dorsal cortex, would produce diffuse OB deafferentation without confounding pathology. Wild type FVB/NJ mice were subjected to mFPI and OB probed for ORN axon degeneration and onset of reactive synaptogenesis. OB extracts revealed 3 d postinjury elevation of calpain-cleaved 150-kDa αII-spectrin, an indicator of axon damage, in tandem with reduced olfactory marker protein (OMP), a protein specific to intact ORN axons. Moreover, mFPI also produced a 3-d peak in GFAP+ astrocyte and IBA1+ microglial reactivity, consistent with postinjury inflammation. OB glomeruli showed disorganized ORN axons, presynaptic degeneration, and glial phagocytosis at 3 and 7 d postinjury, all indicative of deafferentation. At 21 d after mFPI, normal synaptic structure re-emerged along with OMP recovery, supporting ORN afferent reinnervation. Robust 21 d postinjury upregulation of GAP-43 was consistent with the time course of ORN axon sprouting and synapse regeneration reported after more severe olfactory insult. Together, these findings define a cycle of synaptic degeneration and recovery at a site remote to non-contusive brain injury. We show that mFPI models diffuse ORN axon damage, useful for the study of time-dependent reactive synaptogenesis in the deafferented OB.


Assuntos
Axônios/patologia , Axônios/fisiologia , Concussão Encefálica/patologia , Concussão Encefálica/fisiopatologia , Bulbo Olfatório/patologia , Bulbo Olfatório/fisiopatologia , Animais , Astrócitos/patologia , Astrócitos/fisiologia , Modelos Animais de Doenças , Proteína GAP-43/metabolismo , Masculino , Camundongos , Microglia/patologia , Microglia/fisiologia , Regeneração Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Proteína de Marcador Olfatório/metabolismo , Neurônios Receptores Olfatórios/patologia , Neurônios Receptores Olfatórios/fisiologia , Distribuição Aleatória , Espectrina/metabolismo , Sinapses/patologia , Sinapses/fisiologia , Fatores de Tempo
6.
Neurosci Lett ; 653: 31-38, 2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28527714

RESUMO

Although rodent models of traumatic brain injury (TBI) reliably produce cognitive and motor disturbances, behavioral characterization resulting from left and right hemisphere injuries remains unexplored. Here we examined the functional consequences of targeting the left versus right parietal cortex in lateral fluid percussion injury, on Morris water maze (MWM) spatial memory tasks (fixed platform and reversal) and neurological motor deficits (neurological severity score and rotarod). In the MWM fixed platform task, right lateral injury produced a small delay in acquisition rate compared to left. However, injury to either hemisphere resulted in probe trial deficits. In the MWM reversal task, left-right performance deficits were not evident, though left lateral injury produced mild acquisition and probe trial deficits compared to sham controls. Additionally, left and right injury produced similar neurological motor task deficits, impaired righting times, and lesion volumes. Injury to either hemisphere also produced robust ipsilateral, and modest contralateral, morphological changes in reactive microglia and astrocytes. In conclusion, left and right lateral TBI impaired MWM performance, with mild fixed platform acquisition rate differences, despite similar motor deficits, histological damage, and glial cell reactivity. Thus, while both left and right lateral TBI produce cognitive deficits, laterality in mouse MWM learning and memory merits consideration in the investigation of TBI-induced cognitive consequences.


Assuntos
Comportamento Animal , Lesões Encefálicas Traumáticas/fisiopatologia , Modelos Animais de Doenças , Lobo Parietal/lesões , Animais , Lesões Encefálicas Traumáticas/psicologia , Lateralidade Funcional , Hipocampo/fisiopatologia , Masculino , Aprendizagem em Labirinto , Camundongos Endogâmicos C57BL , Neuroglia/fisiologia , Teste de Desempenho do Rota-Rod
7.
Behav Processes ; 114: 78-81, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25680330

RESUMO

B.F. Skinner argued that the science of behavior would progress more rapidly without appealing to theories of learning. He also suggested that theories in a quite different sense were possible, but that the science of behavior as of 1950 was not ready for them. The following analysis distinguishes between Skinner's two concepts of theory. It argues that theory in the second sense has arisen in the quantitative analysis of behavior. The attempt to give a dynamic account of the static regularities of this theory, however, has produced a theory in the first sense. Within its limited domain, this theory offers a rigorous alternative to cognitive accounts of behavior. Rather than distracting attention from actual behavior, it has now led to novel predictions about it. This article is part of a Special Issue entitled 'SQAB 2014'.


Assuntos
Ciências do Comportamento , Filosofia , Teoria Psicológica , Humanos
8.
J Neuropathol Exp Neurol ; 71(3): 198-210, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22318124

RESUMO

Axonal injury is consistently observed after traumatic brain injury (TBI). Prior research has extensively characterized the post-TBI response in myelinated axons. Despite evidence that unmyelinated axons comprise a numerical majority of cerebral axons, pathologic changes in unmyelinated axons after TBI have not been systematically studied. To identify morphologic correlates of functional impairment of unmyelinated fibers after TBI, we assessed ultrastructural changes in corpus callosum axons. Adult rats received moderate fluid percussion TBI, which produced diffuse injury with no contusion. Cross-sectional areas of 13,797 unmyelinated and 3,278 intact myelinated axons were stereologically measured at survival intervals from 3 hours to 15 days after injury. The mean caliber of unmyelinated axons was significantly reduced at 3 to 7 days and recovered by 15 days, but the time course of this shrinkage varied among the genu, mid callosum, and splenium. Relatively large unmyelinated axons seemed to be particularly vulnerable. Injury-induced decreases in unmyelinated fiber density were also observed, but they were more variable than caliber reductions. By contrast, no significant morphometric changes were observed in myelinated axons. The finding of a preferential vulnerability in unmyelinated axons has implications for current concepts of axonal responses after TBI and for development of specifically targeted therapies.


Assuntos
Lesões Encefálicas/patologia , Corpo Caloso/patologia , Fibras Nervosas Amielínicas/patologia , Animais , Axônios/patologia , Axônios/ultraestrutura , Lesões Encefálicas/fisiopatologia , Corpo Caloso/ultraestrutura , Modelos Animais de Doenças , Masculino , Microscopia Eletrônica de Transmissão , Fibras Nervosas Amielínicas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Reflexo/fisiologia , Fatores de Tempo
9.
J Cancer Res Clin Oncol ; 135(1): 141-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18581139

RESUMO

BACKGROUND: There is scarce data on the outcome of young patients aged 35 years and younger, who have been treated with neoadjuvant chemotherapy. The aim of this study is to evaluate the impact of body mass index (BMI) and various prognostic factors on pathologic response and survival in young patients with localized breast cancer. PATIENTS AND METHODS: This is a retrospective evaluation on the outcome of 110 patients who were younger than 35 years at diagnosis and treated with neoadjuvant chemotherapy (CT). Patients were grouped in quartiles of BMI calculated prior to initiation of chemotherapy. Logistic regression analysis was performed to investigate the associations between prognostic variables including BMI and treatment outcome. The impact of prognostic factors on survival was analyzed by Kaplan-Maier and Cox regression tests. RESULTS: Body mass index was not correlated with pathologic complete response (pCR) (n = 13, 11.7%) or survival. Cox regression analysis revealed nodal pCR following neoadjuvant chemotherapy (HR 2.45, P = 0.048) and stage at diagnosis (HR1.99, P = 0.027) as significant independent prognostic factors for DFS, while recurrence was independently associated with shorter OS (HR 169, P = 0.029). CONCLUSION: Body mass index was not correlated with pCR or prognosis in young women with early breast cancer. Pathologic CR was shown to have a significant influence on DFS. Total axillary clearance may be used a surrogate variable in determining prognosis in young patients treated with neoadjuvant chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linfonodos/patologia , Terapia Neoadjuvante , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Índice de Massa Corporal , Neoplasias da Mama/diagnóstico , Quimioterapia Adjuvante , Feminino , Humanos , Metástase Linfática , Prontuários Médicos , Recidiva Local de Neoplasia/diagnóstico , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
10.
Opt Express ; 15(2): 646-51, 2007 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19532287

RESUMO

We demonstrate excitation of whispering gallery modes in optical ring resonators using a gold-clad pedestal planar waveguide structure. The gold-clad structure provides a strong evanescent field for light-coupling into the resonator while enabling low transmission loss throughout much of the visible and near-infrared region. This is advantageous compared to the previously demonstrated anti-resonant reflecting optical waveguide (ARROW) structure, which can only transmit a narrow wavelength band. We show that the height of the pedestal waveguide can be designed to optimize the coupling conditions for the ring resonator. This technology enhances the practicality of optical ring resonators for sensing devices, laser systems, and many other important applications.

11.
Appl Opt ; 45(20): 4927-32, 2006 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-16807601

RESUMO

Bragg grating reflectors etched in amorphous silicon overlay films have been integrated with Ti:LiNbO3 optical waveguides to obtain a narrow (0.05 nm) reflectance spectrum with a > 20 dB dip in the transmittance spectrum. These results were realized at a wavelength of 1542.7 nm for TE polarization on an x-cut, y-propagating substrate with gratings etched to a depth of approximately 93 nm in a 105 nm thick silicon film over a length of 12.5 mm. The reflectance in the channel waveguides is found to be strongly dependent on the depth of the etched grating. The effect of the Bragg waveguide loss factor on the transmittance and reflectance spectra is investigated by using a model for contradirectional coupling that includes an attenuation coefficient. The values for coupling constants kappa and amplitude attenuation constants alpha of samples etched for different time durations to control the grating depths are obtained from the model through the use of the depth of the dips in the transmittance spectra and the spectral widths of the reflectance peaks. It is concluded that the corrugated Si overlay film increases the insertion loss by approximately 2.7 dB, and the loss is not significantly affected by the grating depth.

12.
J Clin Oncol ; 23(28): 7013-23, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16145068

RESUMO

PURPOSE: To determine the response, failure-free survival (FFS), and overall survival rates and toxicity of rituximab plus an intense chemotherapy regimen in patients with previously untreated aggressive mantle-cell lymphoma (MCL). PATIENTS AND METHODS: This was a prospective phase II trial of rituximab plus fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD; considered one cycle) alternating every 21 days with rituximab plus high-dose methotrexate-cytarabine (considered one cycle) for a total of six to eight cycles. RESULTS: Of 97 assessable patients, 97% responded, and 87% achieved a complete response (CR) or unconfirmed CR. With a median follow-up time of 40 months, the 3-year FFS and overall survival rates were 64% and 82%, respectively, without a plateau in the curves. For the subgroup of patients < or = 65 years of age, the 3-year FFS rate was 73%. The principal toxicity was hematologic. Five patients died from acute toxicity. Four patients developed treatment-related myelodysplasia/acute myelogenous leukemia, and three patients died while in remission from MCL. A total of eight treatment-related deaths (8%) occurred. CONCLUSION: Rituximab plus hyper-CVAD alternating with rituximab plus high-dose methotrexate and cytarabine is effective in untreated aggressive MCL. Toxicity is significant but expected. Because of the shorter FFS concurrent with significant toxicity in patients more than 65 years of age, this regimen is not recommended as standard therapy for this age subgroup. Larger prospective randomized studies are needed to define the role of this regimen in the treatment of MCL patients compared with existing and new treatment modalities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Célula do Manto/tratamento farmacológico , Administração Oral , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Rituximab , Resultado do Tratamento , Vincristina/administração & dosagem
13.
Cancer ; 104(2): 345-53, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15948158

RESUMO

BACKGROUND: Myelosuppression and immunosuppression occur with purine analogs. The objective of the current study was to investigate the effects of combined fludarabine, mitoxantrone, and dexamethasone (FND) followed by interferon/dexamethasone on myelosuppression (absolute neutrophil counts), immunosuppression (CD4 and CD8 counts), and infectious complications in patients with previously untreated, Stage IV indolent lymphoma. METHODS: Seventy-three patients were treated. All patients received Pneumocystis carinii pneumonia (PCP) prophylaxis. CD4 and CD8 counts, serum immunoglobulin (Ig) levels, and neutrophil counts were correlated with infectious complications. RESULTS: The median follow-up was 6.1 years. Sixty of 73 patients had CD4, CD8, or Ig measurements. The median baseline CD4 count was 764/microL. This CD4 level decreased to 238/microL at 1 year and to 264/microL at 2 years; and it rose to 431/microL by 3 years and to 650/microL at 4 years. CD8 counts did not change significantly. The median baseline serum IgG level was 989 mg/d, decreased to 536 mg/dL at 1 year and to 693 mg/dL at 2 years, and it rose to 949 mg/dL at 3 years and to 1080 mg/dL at 4 years. Fourteen patients (19%) developed Grade 3-4 infections, the majority during FND therapy with neutropenia and/or accompanied by CD4 counts < 200/microL. CD4, CD8, and neutrophil counts did not differ between patients who developed Grade 3-4 infections, Grade 1-2 infections, or no infections. CONCLUSIONS: Most infections with FND occurred during FND, in the setting of neutropenia, often with concurrent low CD4 counts. The overall safety profile for FND was good. However, patients should be monitored for opportunistic infections, and prophylactic antibiotics are recommended, particularly against PCP.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia de Imunossupressão , Linfoma/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Contagem de Linfócito CD4 , Relação CD4-CD8 , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Feminino , Humanos , Infecções/etiologia , Interferons/administração & dosagem , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/uso terapêutico , Neutropenia/etiologia , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico
14.
Mod Pathol ; 18(9): 1165-75, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15920552

RESUMO

In vitro data support a role for the alpha6beta4 integrin in tumor cell migration and invasion, particularly in breast carcinoma cells, but clinical data on this potentially important integrin are limited. The beta4 integrin subunit has been shown to cluster with genes characteristic of basal/myoepithelial cells in cDNA microarray analyses of breast cancer, and the subset of breast cancers with increased expression of genes characteristic of basal/myoepithelial cells appears to be particularly aggressive. The purpose of this study was to determine whether alpha6beta4 integrin expression correlates with aggressive clinicopathologic features of breast cancer and whether expression of this integrin has prognostic significance in early breast cancer. We evaluated tumor expression of the beta4 integrin subunit gene in a cohort of patients with early invasive breast carcinoma by in situ hybridization and correlated expression levels with multiple clinicopathologic characteristics. We also evaluated expression of laminin-5 protein, the principal ligand of alpha6beta4, in this patient cohort. Although we observed a slight trend towards decreased disease-free survival for patients whose tumors had high beta4 gene expression and coexpression of laminin-5, this did not reach statistical significance (P=0.11). However, we did observe a correlation between beta4 mRNA expression and both tumor size (P=0.01) and tumor nuclear grade (P<0.01). These results do not demonstrate prognostic significance for beta4 gene expression and/or laminin-5 protein expression in early breast cancer, but increased beta4 gene expression in larger tumors and in higher grade tumors does support a potential role for the alpha6beta4 integrin in tumor progression.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Expressão Gênica , Integrina alfa6beta4/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Moléculas de Adesão Celular/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Integrina alfa6beta4/genética , Pessoa de Meia-Idade , Prognóstico , Subunidades Proteicas/biossíntese , Subunidades Proteicas/genética , RNA Mensageiro/análise , Estudos Retrospectivos , Análise de Sobrevida , Calinina
15.
Cancer ; 103(10): 2091-8, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15816054

RESUMO

BACKGROUND: T-cell non-Hodgkin lymphomas (T-NHL) are more aggressive and patients have a poorer prognosis compared with patients with the corresponding B-cell lymphomas. Although intensive treatments have been developed, it is unknown whether they are more effective than CHOP chemotherapy (cyclophosphamide, doxorubicin, oncovorin, and prednisone). METHODS: The authors' retrospective study evaluated the clinical outcome of 135 previously untreated patients with T-NHL who were treated at The University of Texas M. D. Anderson Cancer Center (Houston, TX) between 1996 and 2002. Lymphomas with T-cell histologies with the exception of mycosis fungoides were included. RESULTS: The estimated median overall survival was 46 months. Thirty-seven percent of the patients received CHOP therapy, 48% received intensive therapy, and 15% received other therapy. The estimated 3-year overall survival rates were 62% for the patients treated with CHOP therapy and 56% for the patients who received intensive therapy. After the exclusion of patients with anaplastic large cell lymphoma (ALCL), who are known to have a better prognosis than patients with other T-NHLs, the estimated 3-year overall survival rates were 43% for the patients treated with CHOP therapy and 49% for the patients who received intensive therapy. Parameters that may be independent prognostic factors for survival in T-NHL, excluding ALCL, included ECOG performance status > or = 2, beta-2-microglobulin level > 2 mg/L, lactate dehydrogenase level higher than normal, bulky disease > or = 7 cm, and a higher international prognostic index and tumor score. CONCLUSIONS: The current study data suggested that patients treated with intensive therapies did not fare better than those treated with CHOP therapy. New treatment regimens need to be developed for patients with T-NHL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células T/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , L-Lactato Desidrogenase/análise , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma de Células T Periférico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem , Microglobulina beta-2/análise
16.
J Clin Oncol ; 23(16): 3676-85, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15738535

RESUMO

PURPOSE: The objective of this study was to determine whether the addition of trastuzumab to chemotherapy in the neoadjuvant setting could increase pathologic complete response (pCR) rate in patients with human epidermal growth factor receptor 2 (HER2) -positive disease. PATIENTS AND METHODS: Forty-two patients with HER2-positive disease with operable breast cancer were randomly assigned to either four cycles of paclitaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide or to the same chemotherapy with simultaneous weekly trastuzumab for 24 weeks. The primary objective was to demonstrate a 20% improvement in pCR (assumed 21% to 41%) with the addition of trastuzumab to chemotherapy. The planned sample size was 164 patients. RESULTS: Prognostic factors were similar in the two groups. After 34 patients had completed therapy, the trial's Data Monitoring Committee stopped the trial because of superiority of trastuzumab plus chemotherapy. pCR rates were 25% and 66.7% for chemotherapy (n = 16) and trastuzumab plus chemotherapy (n = 18), respectively (P = .02). The decision was based on the calculation that, if study continued to 164 patients, there was a 95% probability that trastuzumab plus chemotherapy would be superior. Of the 42 randomized patients, 26% in the chemotherapy arm achieved pCR compared with 65.2% in the trastuzumab plus chemotherapy arm (P = .016). The safety of this approach is not established, although no clinical congestive heart failure was observed. A more than 10% decrease in the cardiac ejection fraction was observed in five and seven patients in the chemotherapy and trastuzumab plus chemotherapy arms, respectively. CONCLUSION: Despite the small sample size, these data indicate that adding trastuzumab to chemotherapy, as used in this trial, significantly increased pCR without clinical congestive heart failure.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante , Receptor ErbB-2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Estudos Prospectivos , Indução de Remissão , Trastuzumab
17.
Clin Cancer Res ; 10(20): 6779-88, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15501954

RESUMO

The Akt/mammalian target of rapamycin (mTOR)/4E-BP1 pathway is considered to be a central regulator of protein synthesis, involving the regulation of cell proliferation, differentiation, and survival. The inhibitors of mTOR as anticancer reagents are undergoing active evaluation in various malignancies including breast cancer. However, the activation status of the Akt/mTOR/4E-BP1 pathway and its potential roles in breast cancers remain unknown. Thus, we examined 165 invasive breast cancers with specific antibodies for the phosphorylation of Akt, mTOR, and 4E-BP1 by immunohistochemistry and compared them with normal breast epithelium, fibroadenoma, intraductal hyperplasia, and ductal carcinoma in situ. We discovered that the phosphorylation of Akt, mTOR, and 4E-BP1 increased progressively from normal breast epithelium to hyperplasia and abnormal hyperplasia to tumor invasion. Phosphorylated Akt, mTOR, and 4E-BP1 were positively associated with ErbB2 overexpression. Survival analysis showed that phosphorylation of each of these three markers was associated with poor disease-free survival independently. In vitro, we further confirmed the causal relationship between ErbB2 overexpression and mTOR activation, which was associated with enhanced invasive ability and sensitivity to a mTOR inhibitor, rapamycin. Our results, for the first time, demonstrate the following: (a) high levels of phosphorylation of Akt, mTOR, and 4E-BP1 in breast cancers, indicating activation of the Akt/mTOR/4E-BP1 pathway in breast cancer development and progression; (b) a link between ErbB2 and the Akt/mTOR/4E-BP1 pathway in breast cancers in vitro and in vivo, indicating the possible role of Akt/mTOR activation in ErbB2-mediated breast cancer progression; and (c) a potential role for this pathway in predicting the prognosis of patients with breast cancer, especially those treated with mTOR inhibitors.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Proteínas de Transporte/biossíntese , Perfilação da Expressão Gênica , Fosfoproteínas/biossíntese , Proteínas Quinases/biossíntese , Proteínas Tirosina Quinases/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Antibióticos Antineoplásicos/farmacologia , Proteínas de Transporte/metabolismo , Proteínas de Transporte/farmacologia , Proteínas de Ciclo Celular , Proliferação de Células , Progressão da Doença , Feminino , Genes erbB-2 , Humanos , Hiperplasia , Imuno-Histoquímica , Pessoa de Meia-Idade , Invasividade Neoplásica , Fosfoproteínas/metabolismo , Fosfoproteínas/farmacologia , Fosforilação , Proteínas Quinases/metabolismo , Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases/metabolismo , Proteínas Tirosina Quinases/farmacologia , Proteínas Proto-Oncogênicas , Proteínas Proto-Oncogênicas c-akt , Sirolimo/farmacologia , Análise de Sobrevida , Serina-Treonina Quinases TOR
18.
Biol Blood Marrow Transplant ; 10(11): 794-804, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15505610

RESUMO

We assessed the 5-year results of a high-dose cyclophosphamide, carmustine, and thiotepa (CBT) regimen plus autologous hematopoietic stem cell transplantation (AHST) as an adjuvant consolidation therapy for high-risk primary breast cancer patients with > or =10 positive axillary lymph nodes after primary surgery or > or =4 positive axillary lymph nodes after neoadjuvant chemotherapy and surgery. The associations of various potential prognostic factors with the relapse-free survival (RFS) rate and overall survival (OS) rate were determined. Between October 1992 and March 2000, 177 eligible patients (median age, 46 years) were given high-dose CBT followed by AHST. At a median follow-up of 63 months, the acute treatment-related mortality was 4.5%. Estimated 5-year RFS and OS rates were 62% and 68%, respectively, for all patients. For patients with > or =10 positive axillary lymph nodes after primary surgery, the 5-year RFS and OS rates were 71% and 70%, respectively, and for patients with > or =4 positive axillary lymph nodes after neoadjuvant chemotherapy, the 5-year RFS and OS rates were 53% and 66%, respectively. In 2-sided log-rank tests, earlier disease stage, a lower lymph node ratio, and a lower tumor score were associated with a prolonged RFS and OS. In a multivariate proportional hazards model, disease stage and lymph node ratio remained significant. We concluded that high-dose CBT with AHST for high-risk primary breast cancer is feasible, with comparable efficacy to other phase II studies. More than a 50% estimated 5-year survival rate was seen in all high-risk primary breast cancer patients. In accordance with results from recent randomized studies, we need to continue high-dose chemotherapy with AHST for patients with high-risk primary breast cancer in the phase III randomized setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/terapia , Transplante de Células-Tronco Hematopoéticas , Adulto , Antineoplásicos Alquilantes/administração & dosagem , Carmustina/administração & dosagem , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Tiotepa/administração & dosagem , Transplante Homólogo
19.
Cancer ; 101(8): 1760-6, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15386311

RESUMO

BACKGROUND: The current study was performed to determine the incidence of central nervous system (CNS) metastases and to examine associated disease characteristics in a group of patients with locally advanced breast carcinoma (LABC) or inflammatory breast carcinoma (IBC) treated at The University of Texas M. D. Anderson Cancer Center (Houston, TX). METHODS: Seven hundred sixty-eight patients treated with multimodality therapy between 1982 and 2000 in any of 6 neoadjuvant trials were eligible for the current study. Five hundred ninety-two patients (77%) had LABC, and 176 (23%) had IBC. CNS disease was defined as the presence of brain metastases or leptomeningeal disease. Time to detection of CNS disease and overall survival were estimated using the Kaplan-Meier product-limit method, and differences were evaluated using log-rank tests. RESULTS: The median patient age was 48 years. Most tumors were classified as T4 lesions (58%) and exhibited lymph node involvement (78%). Fifty-one percent of all tumors had positive hormone receptor status. At a median follow-up duration of 9.5 years, 61 patients (8%) had developed CNS metastases, with the CNS representing the first site of recurrence for 38 of these 61 (63%). Characteristics associated with the development of CNS metastases over time included negative hormone receptor status (P = 0.03), Grade 3 disease (P = 0.01), and larger tumor size (P = 0.02). The median time to detection of CNS metastases was 2.3 years. Ten patients (16%) remained alive after treatment for CNS metastases. The median survival from the time of diagnosis of CNS metastases was 8 months. CONCLUSIONS: CNS metastases from breast carcinoma were relatively uncommon and were strongly associated with more aggressive clinical presentation. Survival from the time of diagnosis of such metastases generally was short.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal/secundário , Carcinoma Lobular/secundário , Neoplasias do Sistema Nervoso Central/secundário , Antineoplásicos/uso terapêutico , Carcinoma Ductal/terapia , Carcinoma Lobular/terapia , Neoplasias do Sistema Nervoso Central/terapia , Terapia Combinada , Feminino , Humanos , Incidência , Linfonodos/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
20.
J Clin Oncol ; 22(12): 2294-302, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15197190

RESUMO

PURPOSE: To evaluate the use of an alternate, non-cross-resistant adjuvant chemotherapy regimen in women with a poor pathologic response to a preoperative doxorubicin-based regimen. PATIENTS AND METHODS: Patients with locally advanced breast cancer received three cycles of vincristine, doxorubicin, cyclophosphamide, and prednisone (VACP) every 21 days followed by surgery. Patients with less than 1 cm(3) residual tumor at mastectomy received an additional five cycles of VACP. Those with more than 1 cm(3) residual tumor were randomly assigned to receive an additional five cycles of VACP or five cycles of vinblastine, methotrexate with calcium leucovorin rescue, and fluorouracil (VbMF). RESULTS: One hundred ninety-three patients were evaluable. Overall clinical response was seen in 83.4% after three cycles of VACP, whereas the pathologic complete response was 12.2%. One hundred six patients were randomly assigned to VACP or VbMF. Those receiving VbMF achieved higher relapse-free survival (RFS) and overall survival (OS) than those who received additional VACP, although the differences did not reach statistical significance. Initial stage of tumor, clinical complete response, and pathologic complete response were all associated with statistically superior survival rates. CONCLUSION: Clinical and pathologic response to preoperative doxorubicin-based chemotherapy predicted for improved survival in women with operable breast cancer. For those with a poor response to initial neoadjuvant chemotherapy, treatment with VbMF was associated with a trend toward improved RFS and OS compared with those continuing with the doxorubicin regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/terapia , Doxorrubicina/administração & dosagem , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Taxa de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...